CVE-2026-20040 — HIGH (8.8)

Vulnerability Description

A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary commands as root on the underlying operating system of an affected device. This vulnerability is due to insufficient validation of user arguments that are passed to specific CLI commands. An attacker with a low-privileged account could exploit this vulnerability by using crafted commands at the prompt. A successful exploit could allow the attacker to elevate privileges to root and execute arbitrary commands on the underlying operating system.

CVSS Score

8.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

CHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

HIGH

Related Weaknesses (CWE)

CWE-78

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/ci

FAQ

What is CVE-2026-20040?

CVE-2026-20040 is a vulnerability with a CVSS score of 8.8 (HIGH). A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary commands as root on the underlying operating system of an affected device. This...

How severe is CVE-2026-20040?

CVE-2026-20040 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-20040?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.